Beware summer extremes with insulin

With summer arriving in Minnesota and many other places, I'd like to talk about how to manage insulin storage in extreme temperatures such as this season brings.

A number of years ago, I met with a client who used a rapid insulin pen for meal dosing. She shared with me a story of how she attended the county fair on an exceptionally hot day, and had placed her insulin pen in the back pocket of tight jeans and walked around the fairgrounds all day. She used the pen for covering meals eaten at the fair, and her blood sugars were running higher than normal, but she related this to all the junk food. The next day her blood sugars continued to run high and when she took her (rapid) insulin, it didn't seem to affect her blood sugar level at all; in fact, it was like she was taking water instead of insulin. She wondered if the heat had affected her insulin, so she switched to a new insulin (disposable) pen, and soon after her blood sugars started to drop.

Has this or something similar happened to you?

I looked at insulin manufacturers' websites and found that for the majority of all types and brands of insulin, the maximum temperatures recommended are as follows:

Opened room temperature insulin should not exceed 86 F (30 C) with the exception of Lantus, which should not exceed 77 F (25 C).

Store your insulin in the refrigerator, in an insulated case or cooler with a freezable gel pack, or use a cooling wallet. Cooling wallets are available through many diabetes supply companies and keep insulin vials, pens and pumps cool at a safe temperature without the need for refrigeration or ice. The wallets have a liner filled with crystals. The liner is immersed in cold water for 10-15 minutes, and placed back into the wallet, along with the insulin. It works by relying on the process of evaporation for cooling, can keep insulin cool for up to 48 hours, and is reusable.

Remember, after opening a vial of insulin or starting a new insulin pen, the insulin loses its potency and should be thrown away after a certain number of days, depending on the manufacturer's guidelines. Generally, most vials of insulin are good for 28 days after opening with the exception of Levemir (detemir), which is good for 42 days. Other pens are good for 10, 14, 28 or 42 days. Check the medication insert.

Avoid temperature extremes
Never freeze insulin or expose it to extremely hot temperatures or direct sunlight. Never leave it in your car. Never place it directly on ice or an ice pack.

Watch for changes in insulin appearance
Throw away insulin that is discolored or contains solid particles.

What about insulin pumps?
Heat can make proteins like insulin harden, which increases the potential for infusion set occlusions (blockage). If you live in a hot climate and especially if you work outdoors, you may need to pay closer attention to how the heat can affect your insulin. A patient of mine, who is a roofer in Arizona, found that he needed to replace the insulin in his pump reservoir daily to avoid having high blood glucose readings. Using a pump wallet could be another option for people concerned about the effects of heat on their insulin. Also, make sure that the infusion set tubing is tucked in your clothing and not hanging out and exposed to the light and or heat.

Exact same thing just happened to me with a Humalog pen. I normally don't worry about heat, and had the pen in a black pouch on my motorcycle that easily exceeded 100F. That pen has been somewhat useless since then, and now I suspect that the insulin broke down. I'll be more cateful inthe future!

Sam Hokin

July 19, 2013 3:53 a.m.

This is really nice. Thanks for your information.
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Anonymous

July 11, 2013 2:44 a.m.

This is really nice. Thanks for sharing .
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Lisa

May 14, 2013 3:52 p.m.

As I mentioned in the blog, check out the pump wallet by Frio. They have a cooling case for pumps. www.FRIOCase.com

Nancy and Peggy

May 6, 2013 3:58 p.m.

I only recently changed to the pump and although i had an idea that insulin resistance is different in the heat, when we suddenly had a hot day, didnt realise and sat out in the garden for few hours. felt really thirsty and tired - checked bg - 31!! was physically sick not long afer and threw up twice. has anyone got any tips on how to prevent this happening. how to keep insulin cool in the pump?

Lesley

November 13, 2012 4:26 p.m.

I read your stories/ articles and my bloodsugars have been running a little high, i think by reading these i have realized the pen seems a little discolored and i need to switch to a new pen soon. Thank you.

Hannah

August 22, 2012 4:56 p.m.

The Climapack from Kewl Innovations would be an amazing alternative to cold packs and such that can melt or warm up over a short time. With Climapack, you have several days and no worries! Check out kewlinnovations.com for more details.

Sharon

August 21, 2012 2:24 p.m.

Check out http://www.kewlinnovations.com. They have a device that operates on rechargeable batteries and will keep your insulin cool when it's hot and warm when it's cold. It even monitors your insulin temperature when its cooling/heating function is turned off.

Mike

November 28, 2011 3:00 a.m.

Is there any alternative drug to insulin for treatment of inslin dependent diabetes mellitus related osteoporosis?

madhu

November 28, 2011 2:25 a.m.

I want to know more about side effects of insulin in patients with Type I Diabetes mallitus.
Does insulin cure Type I Diabetes Mallitus related osteoporosis?

madhu

June 26, 2011 5:42 a.m.

Thank you for the great advice. :-)

Mary

June 22, 2011 1:05 p.m.

It is so nice to know some one is out there with such excellent feedback on all issues of health.
I always look forward to receiving your updates, and overall information and I learn so much. I also forward articles to those I know with certain conditions.
Bravo Mayo Clinic!!!!

Joan

June 21, 2011 4:52 p.m.

I once left a bottle of insulin out on the coffee table. I didn't think about the fact that the coffee table received lots of direct sunlight when the blinds were open (which they were that day). Even though it was indoors, the direct sun definitely ruined the insulin.

Lisa

March 25, 2010 3:51 a.m.

Hi,
The blog was really a eye opener to me.Never thought that temperature can affect insulin.
I also want to add, that apart from insulin one can also include herbal anti-diabetic pills.These pills contain anti-diabetic herbs like bitter melon, pterocarpus marsupium etc.These pills are purely herbal and are 100% safe.

shail

August 22, 2009 9:02 a.m.

what should be your ideal glucose reading after being on insulin?

Charles

July 23, 2009 3:50 p.m.

Ginette. It sounds like you need your insulin dose adjusted to cover your higher blood glucose readings. Also, you should see a diabetes educator to learn how to adjust your insulin doses based on blood glucose patterns and learn carb counting so you can use an insulin to carb ratio to cover food. This insulin to carb ratio can be figured out by your healthcare provider. This will give you more flexibiliy in your program.

Nancy and Peggy

July 18, 2009 11:27 a.m.

I have been on Lantus (24 units) for now 4 years. My A1C climbed to 7.0 and my doctor put me on fast acting Apidra but only gave me a general guideline of &quot;start with 3 units and go from there&quot;. Is there a formula by which I can determine how much Apidra to inject in relation to my pre-meal blood sugar reading, the number of carbs I am about to eat and the number of units of Apidra I should use????

Ginette B.

June 18, 2009 1:47 p.m.

Starting insulin: your healthcare provider will help you determine when its necessary to start insulin. Individuals with type 1 diabetes have no choice but to be on insulin injections, since their bodies make minimal or no insulin of their own.

Nancy and Peggy

June 12, 2009 1:34 a.m.

how do you know if you need insulin?

christe

June 4, 2009 3:59 p.m.

Hi Gail, if you think your insulin or Byetta may have been exposed to extreme temps, about the only way to know this is to switch to a new pen and if your numbers are much better then it is probably the cause.

Nancy and Peggy

June 2, 2009 1:53 p.m.

i take both lantus insulin pen and byetta pen. The insulin pen is 50mg at bedtime. The Byetta is twice a day once at breakfast and once at supper (10Mg ea) The past few days my sugar reading is out of control........the expiration date is fine on both .....what should I do.........Could one of these have gone bad?

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